NI-DAQmx false duplicate channel error

[BradW]

I have an SCXI chassis w/ a SCXI-1600 and a SCXI-1102 w/ SCXI-1303 accessory.  I created a series of NI-DAQmx global channels for thermocouples, calling them Air Temp0 through 17.  Using NI-DAQmx subvi's I read them.  See a very simplified VI attachment.  The channels individually all check out, but when I try to read the entire group, I get an error -200072 and it says that Air Temp15 and 16 reference the same physical channel, but when I check the channels in MAX, they are indeed different.  Likewise, if you read one at a time and stimulate the various thermocouples, the displayed response is always consistent with the physical channel. I.E., if you heat the right thermocouple, the reading goes up, but if you heat the wrong thermocouple, the reading doesn't go up. 

Using the simple error handler, the error message is:

"Error -200072 occurred at DAQmx Read (Analog 1D Wfm NChan 1Samp).vi

Possible reason(s):

Duplicate channels in the list of physical channels are not supported by this device.

Channel Name: Air Temp15
Duplicate Channel: Air Temp16
Device: SC2Mod2_Mini

Task Name: Air Temp15:16"

Any ideas?

[Logan_K]

I was unable to reproduce this issue in DAQmx 8.0 using the same channel names that you are using. What version of NI-DAQ are you using? What if you try a different series of channel names - like "MyAir Temp0 .. MyAir Temp17"? If this works, then it is possible that the information about the "Air Temp" global channels in MAX is just corrupt for some reason. You could try resetting the DAQmx information in MAX by going to Tools>>NI-DAQmx Configuration>>Reset NI-DAQmx Configuration. Then re-create your chassis and your global channels.

Regards,
Logan

[BradW]

Thank you for your input. It does seem to have been a corruption of the configuration somehow. 

This is one of the things I hate about MAX.  The unexplained and unexplainable corruptions.  And then the usual solution:  "Oh, reinstall everything and try again."  Grr.  This has been going on for years now.

The station had not crashed or otherwise displayed any misbehavior.  The channels were configured by doing the first one and then duplicating it using the MAX "Duplicate" feature.  I then made a set of channels by individually programming each one, with a different name.  I then deleted the troublesome channels and then renamed the new ones to the desired names.  Whaddya know, they work now.  Is this a MAX bug, known or otherwise?  I have 'way too many other things on my plate to be spending 6 hours chasing corruptions like this.  Virtual Instrumentation is supposed to save time.